Warhammer 40,000: Sanctus Reach is a turn-based strategy game that pits the savage Space Wolves against the even more savage Greenskins across ~45 story-driven campaign missions. Both factions come with 30 unique units which you can then personally adjust to better suit your preferred style of warfare. Each of these units will then be further enhanced as they gain experience throughout the various campaign missions, so do make sure to take care of your veterans as they will gladly take care of your enemies for you!
If you're interested in seeing what all of this looks like in gameplay terms, but also learning how Sanctus Reach is even played, I would recommend checking out the recently posted tutorial video. It might seem like a strange choice to showcase this over the launch trailer, but honestly it does a better job of explaining the gameplay premise than the main trailer. Have a look:
I haven't played Sanctus Reach myself, so take the following with more than a couple of grains of salt, but from what I've seen in the Steam reviews it appears to be a fairly niche game. But if you love strategy games set in the Warhammer 40k universe, and you're OK with muddy graphics and some occasionally bizarre UI decisions, then you might just find something of interest in Sanctus Reach.
If you would like to learn more, or just check out a couple of gameplay videos, I would recommend you head over to Steam. And as a final note, here's a couple of images showcasing the two factions: